the number eight.
a group of eight.
Origin of ogdoad
1615–25; < Late Latin ogdoad- (stem of ogdoas) < Greek ogdoás, derivative of ógdoos eighth; see -ad1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a group of eight
Word Origin for ogdoad
C17: via Late Latin from Greek ogdoos eighth, from oktō eight
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012